1. Field of the invention
The present invention relates to a liquid crystal display device.
2. Description of the Related Art
Liquid crystal display devices are widely used as display devices in televisions or information communication terminals such as computers. Such a liquid crystal display device is configured to change the orientation of a liquid crystal material sandwiched between two substrates by changes in an electric field, thus controlling the transmission of light passing through these two substrates and the liquid crystal material to produce images.
In such a liquid crystal display device, it is common to use a lighting device called a “backlight” as a light source. As backlighting systems, a direct-lit backlight, which has light sources behind a liquid crystal display surface, and an edge-lit (side-lit) backlight, which illuminates a liquid crystal display surface by reflecting light emitted from the side, are typically known. The liquid crystal display devices used in recent mobile communication terminals, such as smartphones, are required to be made smaller and consume less power. Thus, the edge-lit backlights including light emitting diodes (LEDs) as light sources have come into use
JP 2014-029798 A discloses a lighting device with an edge-lit backlight that can enhance the efficiency of providing light to a light guide plate to reduce the thickness of the lighting device.
In the above edge-lit backlight, light sources such as LEDs are arranged along any one or more of the four sides of the screen. If more light sources were arranged to increase the brightness, the frame area formed around the display area would be wider to make the display device larger.